The overall objective of the proposed studies is to further characterize proteoglycans that undergo rapid axonal transport in the intact and regenerating goldfish optic nerve. Proteoglycans, as a glycoconjugate class, have become increasingly implicated in neuronal synaptic function and in the development and functional differentiation of neurons. As yet, however, there has been little information gained on the properties of proteoglycans undergoing axonal transport and on changes in proteoglycan transport that may accompany functional characterizing. The proposed studies will address the specific aim of characterizing axonally transporting proteoglycans that are soluble and that are affiliated with various membranous compartments, including synaptic vesicles, synaptic plasma membrane and synaptic junctions. An additional aim is to detect changes in the distribution or turnover of axonally transported proteoglycans that may be correlated with synpatic secretory activity. The final aim is to further characterize changes in axonally transported proteoglycans that have been preliminary shown to accompany regeneration of the optic nerve. All of these studies will employ labeling, ion exchange chromatography, gel filtration chromatography, density gradients, affinity chromatography and enzyme-chemical analysis of polysaccharide (glycosaminoglycan) chains. The results of these studies should clarify the role of proteoglycans in normal synaptic function and in the facilitation of CNS regeneration in the lower vertebrates.